Modular femoral prosthesis system for hip arthroplasty

ABSTRACT

A modular femoral prosthesis system for an orthopaedic hip implant and method of use is disclosed. The prosthesis system includes a femoral stem component and a plurality of collar components configured to be selectively coupled to the stem component in a fixed position adjacent to a neck of the stem component. Each of the collar components includes a base and is configured to secure an assembled femoral prosthesis to a patient&#39;s surgically prepared femur to provide stability for the assembled femoral prosthesis.

This application is a divisional application under 35 U.S.C. § 121claiming priority to U.S. patent application Ser. No. 14/986,433 filedDec. 31, 2015, which is expressly incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates generally to customizable femoralcomponents used in a total hip arthroplasty and more particularly to oneor more collars that may be coupled to a femoral stem of a hipprosthesis.

BACKGROUND

Joint arthroplasty is a well-known surgical procedure by which adiseased and/or damaged natural joint is replaced by a prosthetic joint.For example, in a primary hip arthroplasty surgical procedure, aprosthetic hip replaces a patient's natural hip. In a revision hiparthroplasty surgical procedure, a revision prosthetic hip replaces animplanted primary hip prosthesis. A typical prosthetic hip includes afemoral component and an acetabular component. A typical femoralcomponent includes a stem having a neck and an elongated body extendingdistally from the neck, and a femoral head configured to be positionedon the neck of the stem. The stem of the femoral component is secured toa patient's femur. A typical acetabular component includes an acetabularcup and a liner. The acetabular cup component is secured to thepatient's coxal bone and is formed to receive and secure the femoral

SUMMARY

According to one aspect of the disclosure, a modular femoral prosthesissystem includes a stem component configured to be received in a proximalend of a patient's surgically prepared femur, the stem comprising aneck, an elongated body extending distally from the neck, and a trunnionconfigured to receive a femoral head component extending medially andproximally from the neck, and a plurality of collar componentsconfigured to be selectively coupled to the stem component in a fixedposition adjacent to the neck of the stem component. Each of theplurality of collar components includes a base having an inferiorsurface configured to contact a surgically prepared proximal surface ofthe patient's femur. The plurality of collar components including afirst collar component having the base, the base of the first collarcomponent having a platform and a pair of arms extending away from alateral end of the platform, and a second collar component including thebase and a flange extending away from a lateral end of the base, theflange being configured to secure the second collar component in a fixedposition relative to a trochanter of the patient.

In some embodiments, each collar component of the modular femoralprosthesis system is made of a material different than the stemcomponent. The stem component is made of a metallic material and eachcollar component is made of a biocompatible polymeric material. Thebiocompatible polymeric material is polyether ether ketone (PEEK).

In some embodiments, the trunnion defines a longitudinal axis thatextends through the neck of the stem component, the stem componentfurther comprises a shoulder positioned between the elongated body andthe neck, and each collar component is configured to be coupled to theshoulder such that the inferior surface of the base of each collarcomponent extends transverse to the longitudinal axis defined by thetrunnion. The shoulder includes an anterior surface, a posterior surfacepositioned opposite the anterior surface, and a medial surfacepositioned inferior of the neck and extending between the anterior andposterior surface, a groove defined in the anterior surface, theposterior surface, and the medial surface of the shoulder, the grooveextending transverse to the longitudinal axis of the trunnion and beingconfigured to receive the base of each collar component to secure eachcollar component to the stem component. When the first collar componentis coupled to the stem component, each of the pair of arms is receivedinto the groove defined in the shoulder of the stem component. When thesecond collar component is coupled to the stem component, an innersurface of the base is received into the groove defined in the shoulderof the stem component. The groove includes an anterior channel extendingalong the anterior surface of the shoulder and a posterior channelextending along the posterior surface of the shoulder, and each channelextends from a first open end defined in the medial surface of theshoulder to a second open end defined in a superior, lateral surface ofthe shoulder. A socket sized to receive an insertion tool is defined inthe superior, lateral surface of the shoulder.

In some embodiments of the modular femoral prosthesis system, eachcollar component is configured to be coupled to the stem component via apress-fit. In yet other embodiments, the modular femoral prosthesissystem also includes a fastener configured to couple each collarcomponent to the stem component. In some embodiments, the platform ofthe first collar component defines a maximum anterior-posterior width,and the pair of arms of the first collar component defines a maximumanterior-posterior width that is less than the maximumanterior-posterior width of the platform. In some embodiments, theplatform of the first collar component includes a curved outer surfacethat extends from an inferior surface to a superior surface of the firstcollar component, the curved outer surface extending from a first endconnected to an anterior arm of the pair of arms to a second endconnected to a posterior arm of the pair of arms.

According to another aspect, an orthopaedic femoral prosthesis includesa femoral stem component configured to be received in a proximal end ofa patient's surgically prepared femur, the stem comprising a neck, anelongated body extending distally from the neck, and a trunnionconfigured to receive a femoral head component extending medially andproximally from the neck, and a collar component configured to becoupled to the stem component in a fixed position relative to the stemcomponent. The collar component including a base and a flange, the basehaving a superior surface extending between a medial end of the base anda lateral end of the base, an inferior surface positioned opposite thesuperior surface, and an inner wall extending between a first openingformed in the superior surface and a second opening formed in theinferior surface to define a slot sized to receive the stem component.The flange extends away from the lateral end of the base and forms anon-orthogonal angle with the superior surface of the base, and theflange is configured to couple the stem component in a fixed positionrelative to the patient's trochanter.

In some embodiments, the flange of the collar component extendssuperiorly away from the elongated body of the stem when the collarcomponent coupled to the stem component. In some embodiments, thetrunnion defines a longitudinal axis that extends through the neck ofthe stem component, and the collar component is configured to be coupledto the stem component such that the inferior surface of the collarcomponent extends transverse to the longitudinal axis of defined by thetrunnion. In some embodiments, the stem component further comprises agroove formed therein, the groove being sized to receive the inner wallof the collar component when the collar component is secured to the stemcomponent.

According to another aspect, a method for performing a hip arthroplastyis disclosed. The method including resecting a proximal end of apatient's femur to form a planar proximal surface, selecting a femoralstem component having a neck, an elongated body extending distally fromthe neck, and a trunnion configured to receive a femoral head componentextending medially and proximally from the neck, inserting a broachthrough the planar proximal surface to define a passageway sized toreceive the selected femoral stem component, selecting a collarcomponent from a plurality of collar components, each collar componentincluding an inferior surface configured to engage the planar proximalsurface of the patient's femur, securing the selected collar componentto the femoral stem component such that the inferior surface of thecollar component extends transverse to a longitudinal axis of thetrunnion of the femoral stem component, and implanting the femoral stemcomponent in the patient's femur such that the inferior surface of theselected collar component engages with the planar proximal surface ofthe patient's femur.

In some embodiments, selecting the collar component further includesselecting a first collar component from the plurality of collarcomponents, the first collar component including a base having theinferior surface configured to contact a surgically prepared proximalsurface of the patient's femur, the base comprising a platform and apair of arms extending away from a lateral end of the platform, the pairof arms cooperating to form a slot having an opening defined at alateral end of the base, the slot being sized to receive the stemcomponent, and securing the selected collar component to the femoralstem component further includes advancing the first collar componentalong a groove axis defined by a groove formed in the stem component,the groove axis extending transverse to the longitudinal axis defined bythe trunnion. Advancing the first collar component further includesadvancing the first collar component along the groove axis until theinner surface of the first collar component engages with the groovesurface of the stem component.

In some embodiments, selecting the collar component further includesselecting a second collar component from the plurality of collarcomponents, the second collar component including a base having theinferior surface configured to contact a surgically prepared proximalsurface of the patient's femur and defining a slot sized to receive thestem component and a flange extending away from a lateral end of thebase, the flange being configured to secure the second collar componentin a fixed position relative to a trochanter of the patient. Securingthe selected collar component to the femoral stem component furtherincludes inserting a distal tip of the stem component into the slot ofthe second collar component, advancing the second collar componentproximally along a body axis defined in the stem component, and engaginga groove surface that defines a groove formed in the stem component withthe inner surface of the second collar component. The method may furtherinclude securing a trochanteric reattachment device to the patient'strochanter, the trochanteric reattachment device including a body and aplurality of cables, threading the plurality of cables through aplurality of passageways extending through the flange of the secondcollar component, and securing the threaded cables to the body of thetrochanteric reattachment device.

BRIEF DESCRIPTION OF THE DRAWINGS

The detailed description particularly refers to the following figures,in which:

FIG. 1 is a perspective view of an embodiment of a femoral prosthesissystem including a femoral stem component and a plurality of collarcomponents for use with the stem component;

FIG. 2 is a bottom plan view of one of the collars of FIG. 1;

FIG. 3 is a top plan view of another of the collars of FIG. 1;

FIG. 4 is a side elevation view of the another collar of FIG. 3;

FIG. 5 is a cross-sectional view of the stem component of FIG. 1 takenalong the line 5-5 in FIG. 1;

FIG. 6 a simplified block diagram of a method for implanting a femoralprosthesis assembly assembled from the femoral prosthesis system of FIG.1;

FIG. 7 is a perspective view of an embodiment of a femoral prosthesisassembly including one of the collars of FIG. 1 coupled to the stemcomponent of FIG. 1;

FIG. 8 is a partially cut-away view of the femoral prosthesis assemblyof FIG. 7 implanted in a patient's femur;

FIG. 9 is a perspective view of the assembled femoral prosthesisassembly of FIG. 7 implanted in a patient's femur;

FIG. 10 is a perspective view of an embodiment of another femoralprosthesis assembly including another of the collars of FIG. 1 andcoupled to the stem component of FIG. 1;

FIG. 11 is a partially cut-away view of the femoral prosthesis assemblyof FIG. 10 implanted in a patient's femur;

FIG. 12 is a perspective view of another embodiment of a femoralprosthesis system including a femoral stem component and a plurality ofcollars for use with the stem component;

FIG. 13 is a bottom plan view of one of the collars of FIG. 12;

FIG. 14 is a side elevation view of the collar of FIG. 13;

FIG. 15 is a bottom plan view of another of the collars of FIG. 12;

FIG. 16 is a side elevation view of the collar of FIG. 15;

FIG. 17 is a cross-sectional view of the stem component of FIG. 12 takenalong the line 15-15 in FIG. 12;

FIG. 18 is a perspective view of an embodiment of a femoral prosthesisassembly including one of the collars of FIG. 12 coupled to the stemcomponent of FIG. 12;

FIG. 19 is a perspective view of another embodiment of a femoralprosthesis assembly including another of the collars of FIG. 12 coupledto the stem component of FIG. 12;

FIG. 20 is a perspective view of another embodiment of a femoralprosthesis system including a femoral stem component, a plurality ofcollars for use with the stem component, and a fastener;

FIG. 21 is a cross-sectional view of a femoral prosthesis assemblyincluding the stem component of FIG. 20, one of the collars of FIG. 20,and the fastener of FIG. 20 taken along the line 21-21 in FIG. 20;

FIG. 22 is a perspective view of another embodiment of a femoralprosthesis system including a femoral stem component, a collar for usewith the stem component, and a fastener;

FIG. 23 is a cross-sectional view a femoral prosthesis assemblyincluding the stem component of FIG. 22, the collar of FIG. 22, and thefastener of FIG. 22 taken along the line 23-23 in FIG. 22; and

FIG. 24 is a perspective view of the femoral prosthesis assembly of FIG.23.

DETAILED DESCRIPTION OF THE DRAWINGS

While the concepts of the present disclosure are susceptible to variousmodifications and alternative forms, specific exemplary embodimentsthereof have been shown by way of example in the drawings and willherein be described in detail. It should be understood, however, thatthere is no intent to limit the concepts of the present disclosure tothe particular forms disclosed, but on the contrary, the intention is tocover all modifications, equivalents, and alternatives falling withinthe spirit and scope of the invention as defined by the appended claims.

References in the specification to “one embodiment”, “an embodiment”,“an example embodiment”, etc., indicate that the embodiment describedmay include a particular feature, structure, or characteristic, butevery embodiment may not necessarily include the particular feature,structure, or characteristic. Moreover, such phrases are not necessarilyreferring to the same embodiment. Further, when a particular feature,structure, or characteristic is described in connection with anembodiment, it is submitted that it is within the knowledge of oneskilled in the art to effect such feature, structure, or characteristicin connection with other embodiments whether or not explicitlydescribed.

Referring to FIG. 1, a modular femoral prosthesis system 10 of a hipprosthesis is shown. The femoral prosthesis system 10 may be utilized toassemble a femoral prosthesis 12 customized to the needs of eachpatient. The femoral prosthesis system 10 includes a femoral stemcomponent 16 that is configured to be implanted into the medullary canalof a patient's femur 130, a femoral head component 18 configured to beattached to the femoral stem component 16, and a plurality of modularcollar components 14 configured to be separately and selectively securedto the femoral stem component 16. In use, an orthopaedic surgeon mayassemble a femoral prosthesis 12 using the various components beforeimplanting the assembled femoral prosthesis 12 in the patient's femur130. For example, in some patients, the femoral prosthesis 12 mayinclude only the stem component 16 and the femoral head component 18.For other patients, the orthopaedic surgeon may couple one of the collarcomponents 14 to the stem component 16 to address specific additionalneeds of a patient, as described in greater detail below.

In the illustrative embodiment of FIG. 1, the collar components 14include a stabilizing collar 22 and a trochanter collar 24 that may beselectively secured to the femoral stem component. As described ingreater detail below, each collar component 14 is configured to becoupled to the stem component 16 in a fixed, immoveable positionrelative to the stem component 16. When the femoral prosthesis 12 isimplanted, each collar component 14 is configured to engage thepatient's femur 130 to provide additional stability for the femoralprosthesis 12. It should be appreciated that in other embodiments theplurality of collar components 14 of the femoral prosthesis system 10may include additional collar configurations, including collarcomponents of different sizes and shapes.

Although the system 10 may include a number of stem components 16 andfemoral head components 18 of different sizes, the collar components 14permit each stem component 16 to be customized based on the needs of aparticular patient. In the illustrative embodiment, each stem component16 may be used in one of three different configurations in a primary hiparthroplasty or in a revision hip arthroplasty. In that way, the numbercomponents in a surgical system may be reduced.

The illustrative stem component 16 is formed from an implantablemetallic material such as, for example, stainless steel, cobaltchromium, or titanium. The femoral head component 18 is similarly formedfrom an implantable metallic material such as, for example, stainlesssteel, cobalt chromium, or titanium. In an illustrative embodiment, eachcollar component 14 is formed from a resorbable material that may beassimilated into the body over time. In the illustrative embodiment,each collar component 14 is made of a rigid polymer such aspolyetheretherketone (PEEK). As a result, each collar component 14 iscapable of providing more stability than a stem component 16 alone andis easier to manipulate in the event that a revision hip replacement isnecessary. In other embodiments, one or more of the collar components 14may be formed from a medical-grade metallic material such as stainlesssteel, cobalt chrome, or titanium, although other metals or alloys maybe used.

As shown in FIG. 1, the femoral head component 18 includes asubstantially spherical outer surface 20, which is configured to engagea corresponding bearing surface of an acetabular prosthetic component(not shown). An acetabular prosthetic component generally includes anouter shell configured to engage the acetabulum of the patient and aninner bearing or liner coupled to the shell that is configured to engagethe femoral head component 18 to form a ball and socket joint thatapproximates the natural hip joint.

As shown in FIG. 1, the stem component 16 includes a neck 26, anelongated body 28 configured to be received in a surgically-preparedcavity of the patient's femur 130, and a trunnion 30 extendingsuperiorly and medially from the neck 26. A shoulder 32 connects theneck 26 to the elongated body 28. As described in greater detail below,the shoulder 32 is configured to be secured to one of the collarcomponents 14.

The elongated body 28 extends distally from the shoulder 32 to a distaltip 160. In the illustrative embodiment, the elongated body 28 is shapedto engage the patient's bone via a press-fit to secure the stemcomponent 16 to the patient's femur. In other embodiments, the elongatedbody 28 may be secured via other attachment means such as, for example,bone cement.

The trunnion 30 is shaped to be received in a matching bore (not shown)of the femoral head component 18. In the illustrative embodiment, thebore and the trunnion 30 are tapered such that the femoral headcomponent 18 may be secured to the stem component 16 via a Morse taperlocking connection. In other embodiments, the trunnion 30 and thesurface lining the bore of the femoral head component 18 may bethreaded. As shown in FIG. 1, the trunnion 30 defines a longitudinalaxis 45 that extends through its proximal end surface.

The shoulder 32 of the stem component 16 includes a medial surface 34that is positioned inferior of the neck 26 and the trunnion 30, ananterior surface 36, and a posterior surface 38 positioned opposite theanterior surface 36. In the illustrative embodiment, the medial surface34 connects the surfaces 36, 38. As shown in FIG. 1, the shoulder 32also includes a superior, lateral surface 40 that extends between thesurfaces 36, 38. In the illustrative embodiment, a socket 42 is definedin the lateral surface 40. The socket 42 is sized to receive aninsertion tool (not shown), which may be used to implant the stemcomponent 16 in the patient's femur 130.

As described above, the shoulder 32 is configured to be secured to oneof the collar components 14. In the illustrative embodiment, the stemcomponent 16 includes a groove 44 that is sized to receive portions ofeach collar component 14 to secure the collar component 14 to the stemcomponent 16 via a press-fit connection. In other embodiments, otherfastening means may be used to secure the collar component 14 to thestem component 16, including the exemplary methods described below inregard to FIGS. 20-21. For example, a collar component may be coupled tothe femoral stem component via a press-fit, bio-compatible medical gradeepoxy, medical grade cement, a fastener, a snap fit mechanism, or may bemolded to the femoral stem component.

As shown in FIGS. 1 and 5, the groove 44 includes a pair of channels 50,52 that are defined in the anterior surface 36 and the posterior surface38, respectively, of the shoulder 32. The channels 50, 52 extend fromopen ends 46 defined in the medial surface 34 to open ends 48 defined inthe superior, lateral surface 40. Each channel 50, 52 extends along alongitudinal axis 55 extending transverse to the longitudinal axis 45 ofthe trunnion 30. In the illustrative embodiment, the longitudinal axis55 of each channel 50, 52 extends orthogonal to the longitudinal axis45. In other embodiments, the longitudinal axis of the channels extendsat non-orthogonal angles relative to the longitudinal axis 45. As shownin FIG. 5, each channel 50, 52 is defined by base walls 54 that extendinwardly from openings defined the surfaces 36, 38. The channels 50, 52illustratively have rectangular cross-sections, but it should beappreciated that in other embodiments cross-sections of other geometricshapes (e.g., curved) may be used. Additionally, as shown in FIG. 5,each channel 50, 52 extends along a straight axis 55; it should beappreciated that in other embodiments one or both of the channels 50, 52may extend partially or wholly along a curved axis.

As described above and shown in FIG. 1, the system 10 includes astabilizing collar 22 and a trochanter collar 24, which are configuredto be selectively coupled to the stem component 16. In the illustrativeembodiment, each of the collars 22, 24 is configured to engage asurgically prepared proximal surface 132 of the patient's femur 130 whenthe femoral prosthesis 12 is positioned in the patient's femur 130. Inother embodiments, however, the trochanter collar 24 may not engage thesurgically prepared proximal surface of the patient's femur 130 and maybe configured to only engage a portion of the patient's trochanter 134.

In the illustrative embodiment, each of the collars 22, 24 includes abase 56 that is configured to engage with the stem component 16. Thebase 56 includes a superior surface 58, an inferior surface 60positioned opposite the superior surface 58, and an outer surface 62that defines an outer edge of the each collar and extends between thesuperior surface 58 and the inferior surface 60. The inferior surface 60of each collar is configured to engage the surgically prepared proximalsurface 132 of the patient's femur 130. Each base 56 also includes aninner wall 64 extending from the superior surface 58 to the inferiorsurface 60 to define a slot 66. In the illustrative embodiment, theinner wall 64 of each of the collars 22, 24 is configured to engage thebase walls 54 defining the channels 50, 52 to secure the collar to thestem component 16 via a press-fit or an interference fit. Additionally,as shown in FIGS. 1-4, the base 56 of each illustrative collar component14 is planar; it should be appreciated that in other embodiments thebase 56 may be curved or partially curved.

As shown in FIG. 2, the stabilizing collar 22 has an opening 68 formedat a lateral end 70 of its base 56 such that the slot 66 is anopen-ended slot. In other embodiments, the slot of the stabilizingcollar 22 may be a closed slot, similar to the slot of the trochantercollar 24 described below. The base 56 includes a platform 72 that ispositioned opposite the opening 68 and a pair of arms 74, 76 that extendlaterally from the platform 72 along the slot 66. The platform 72includes a curved outer surface 80 that extends between the inferiorsurface 60 and the superior surface 58 of the base 56. The curved outersurface 80 extends from a first end 82 connected to an anterior arm 74to a second end 84 connected to a posterior arm 76 of the pair of arms.In the illustrative embodiment, the platform 72 of the stabilizingcollar 22 defines a maximum anterior-posterior width 86 that is greaterthan a maximum anterior-posterior width 88 defined by the pair of arms74, 76 of the base 56. In other embodiments, the maximumanterior-posterior width 86 of the platform 72 is equal to or less thanthe maximum anterior-posterior width 88 of the pair of arms 74, 76.

As shown in FIG. 3, the illustrative slot 66 of the trochanter collar 24is surrounded by the inner wall 64 such that the slot 66 is a closedslot. The trochanter collar 24 includes the base 56 and a flange 90extending away from a lateral end 92 of the base 56. The flange 90 ofthe trochanter collar 24 includes a medial surface 94, a lateral surface96 positioned opposite the medial surface 94, and an outer surface 98that connects the surfaces 94, 96. As shown in FIG. 4, the medialsurface 94 extends away from the superior surface 58 of the base 56 andcooperates with the superior surface 58 to define an angle 100. In theillustrative embodiment, the angle 100 is a non-orthogonal anglerelative to the superior surface 58 of the base 56. When the trochantercollar 24 is coupled to the stem component 16, the flange 90 extendssuperiorly away from elongated body 28 of the stem component 16 (seeFIG. 10).

Returning to FIG. 3, the trochanter collar 24 has a plurality ofpassageways 102 that extend through the flange 90. Each passageway 102is configured to cooperate with a trochanteric reattachment device 162(see FIG. 11) to couple the femoral prosthesis 12 in a fixed positionrelative to the trochanter 134 of the patient's femur 130. An example ofa trochanteric reattachment device 162 may be the TrochantericReattachment Device produced and distributed by DePuy Synthes Products,Inc., of Raynham Mass. In the illustrative embodiment, the passageways102 are sized to receive cables 166 of the trochanteric reattachmentdevice 162. It should be appreciated that in other embodiments thetrochanter collar 24 may include additional passageways or thepassageways may be omitted.

Referring now to FIG. 6, a method 140 for performing a hip arthroplastyis shown. At block 142, an orthopaedic surgeon, or other member of asurgical team, may resect a proximal end of a patient's femur 130 toform a planar proximal surface 132 as shown in FIGS. 8 and 9. Asdescribed above, the femoral prosthesis 12 may include a stem component16 and a femoral head component 18. Depending on the needs of thepatient, the surgeon may also include the stabilizing collar 22 ortrochanter collar 24 in the femoral prosthesis 12. In some embodiments,such as the case in some revision hip arthroplasties, an orthopaedicsurgeon will also prepare medial surface of a trochanter 134 of thepatient's femur 130, as shown in FIG. 11. At block 144, the orthopaedicsurgeon selects a stem component 16 and a femoral head component 18based on surgical parameters determined before the surgical operationbegan and intra-operative data determined during the surgical operation.

At block 146, the orthopaedic surgeon may insert a broach through theplanar proximal surface 132 of the patient's femur to define apassageway 136 in the intramedullary canal of the patient's femur 130sized to receive the selected femoral stem component 16. The passagewayis shown in FIGS. 8 and 11. The size of the broach used by theorthopaedic surgeon is determined based on the size of the selectedfemoral component.

At block 148, the orthopaedic surgeon determines whether the femoralprosthesis 12 requires more stability than what is provided by the stemcomponent 16 alone. If the femoral prosthesis 12 does not requireadditional stability, the surgeon may continue to block 154 in which thestem component 16 and the femoral head component 18 are implanted in thepatient's femur 130. If additional stability is required, the surgeoncontinues to block 150 in which the surgeon selects a collar from theplurality of collars 14 to couple to the stem component 16. Each of thecollars of the plurality of collars includes an inferior surface 60configured to engage the planar proximal surface 132 of the patient'sfemur 130. The plurality of collars 14 may include a number of differenttypes of collars configured to provide different types of stability. Forexample, the stabilizing collar 22 includes a platform that provides alarge surface area to engage the planar proximal surface 132 of thepatient's femur 130. In another example, the trochanter collar 24includes a flange 90 configured to couple a trochanter 134 of thepatient's femur 130 to the femoral prosthetic assembly.

At block 152, the orthopaedic surgeon may secure the selected collar tothe stem component 16 such that the inferior surface 60 of the collarextends transversely to the longitudinal axis 45 of the stem component16 (See FIGS. 7 and 10). As will be discussed in more detail below, theplurality of collars 14 may be coupled to the stem component 16 in avariety of different ways.

At block 154, once the selected collar is secured in a fixed positionrelative to the stem component 16, the assembled femoral prosthesis 12is positioned and implanted in the patient's femur 130 such that theinferior surface 60 of the selected collar engages with the planarproximal surface 132 of the patient's femur 130 (See FIGS. 8 and 11).The proper positioning of the femoral prosthesis 12 depends on theselected collar that has been coupled to the stem component 16. In someembodiments, such as in the case of the trochanter collar 24, additionalsteps are taken to secure the collar to other parts of the patient'sfemur 130.

As discussed above, each of the collar components 14 may be coupled tothe stem component 16 in a number of different ways. As shown in FIG. 7,the illustrative stabilizing collar 22 is coupled to the stem component16 by advancing the stabilizing collar 22 into the groove 44 of the stemcomponent 16. The groove 44 includes two channels 50, 52, each having alongitudinal axis 55 that extends transversely to the longitudinal axis45 of the trunnion 30. To couple the stabilizing collar 22 to the stemcomponent 16, the lateral end 70 of the stabilizing collar 22 isadvanced along the longitudinal axis 55 defined by the channels 50, 52.As the stabilizing collar 22 is advanced along the longitudinal axis 55,the stem component 16 passes through the opening 68 of the stabilizingcollar 22 and into the slot 66 of the stabilizing collar 22. The groove44 receives the plurality of arms 74, 76 of the stabilizing collar 22.The stabilizing collar 22 is advanced until the inner wall 64 of thestabilizing collar 22 engages the base walls 54 that define the groove44 formed in the stem component 16. As discussed above, in theillustrative embodiment, the stabilizing collar 22 is coupled to thestem component 16 via a press-fit.

As shown in FIG. 8, once the stabilizing collar 22 is coupled to thestem component 16, the femoral prosthesis 12 is inserted into thebroached intramedullary canal of the patient's femur 130. The femoralprosthesis 12 is positioned such that the inferior surface 60 of thestabilizing collar 22 contacts the surgically prepared proximal surface132 of the patient's femur 130. In this way, the stabilizing collar 22provides stability to the femoral prosthesis 12 while the patient'snatural bone grows around the femoral prosthesis 12.

To couple the trochanter collar 24 to stem component 16, the distal tip160 of the stem component 16 is inserted into the slot 66 of thetrochanter collar 24. The trochanter collar is advanced proximally upthe stem component 16 along a body axis 158 that extends along theelongated body 28 of the stem component 16. As shown in FIG. 10, thetrochanter collar 24 is coupled to the stem component 16 by positioningthe base 56 of the trochanter collar 24 in the groove 44 of the stemcomponent 16. When so coupled, the inner wall 64 of the trochantercollar 24 engages the base walls 54 that define the groove 44 formed inthe stem component 16.

As shown in FIG. 11, the femoral prosthesis 12 that includes thetrochanter collar 24 is secured to the trochanter 134 of the patient'sfemur 130 using a trochanteric reattachment device 162. An embodiment ofthe trochanteric reattachment device 162 includes a body 164 configuredto be coupled to the trochanter 134 of the patient's femur 130 and aplurality of cables 166 extending from the body 164. The cables 166include a first end 168 secured to the body and a second end 170. Thesecond end 170 of the cables 166 are threaded through the passageways102 formed in the flange 90 of the trochanter collar 24. The second end170 of the cables 166 are then secured to the body 164. In this way, thefemoral prosthesis 12 is securely engaged with the trochanter 134 of thepatient's femur 130.

In some embodiments, the groove 44 and the plurality of collars 14 mayinclude complimentary features to couple the plurality of collars 14 tothe stem component 16. For example, the groove 44 may include a flangethat mates with a corresponding aperture formed in the plurality ofcollars 14, or vice versa. In other embodiments, the plurality ofcollars 14 may be coupled to the stem component 16 by a fasteningdevice, such as a clip or a screw.

Referring now to FIGS. 12-19, another embodiment of a modular femoralprosthesis system (hereinafter system 210) of a hip prosthesis is shown.Some of the features of FIGS. 12-19 are similar to the featuresdescribed in the embodiment shown in FIGS. 1-11. For such features, thereference numbers from the embodiment described above will be used toidentify those features in FIGS. 12-19. Like the embodiment of FIGS.1-11, the femoral prosthesis system 210 may be utilized to assemble afemoral prosthesis 212 customized to the needs of each patient.

The femoral prosthesis system 210 includes a femoral stem component 216configured to be implanted into a patient's femur 130, the femoral headcomponent 18 configured to be attached to the femoral stem component216, and a plurality of modular collar components 214 configured to beseparately and selectively secured to the femoral stem component 216. Inuse, an orthopaedic surgeon may assemble a femoral prosthesis 212 usingthe various components before implanting the assembled femoralprosthesis 212 in the patient's femur 130 (see FIGS. 18-19).

As shown in FIG. 12, the stem component 216 includes the neck 26, theelongated body 28 configured to be received in a surgically-preparedcavity of the patient's femur 130, and the trunnion 30 extendingsuperiorly and medially from the neck 26. The shoulder 32 connects theneck 26 to the elongated body 28 and is configured to be secured to oneof the collar components 214. In the illustrative embodiment, the stemcomponent 216 includes a groove 220 positioned in the shoulder 32 thatis sized to receive portions of each collar component 214. The groove220 is configured to secure the collar component 214 to the stemcomponent 216 via a mechanical connection.

As shown in FIGS. 12 and 17, the groove 220 includes a pair of channels50, 52 that are defined in the anterior surface 36 and the posteriorsurface 38, respectively, of the shoulder 32. The channels 50, 52 extendfrom open ends 46 defined in the medial surface 34 of the shoulder 32.Each channel 50, 52 extends along the longitudinal axis 55 that extendstransversely to the longitudinal axis 45 of the trunnion 30. As shown inFIG. 17, each of the channels 50, 52 is defined by base walls 54 thatextend inwardly from openings defined the surfaces 36, 38. The basewalls 54 include a planar bottom surface 222 that extends transverselyto the longitudinal axis 45 of the trunnion 30, a curved top surface224, and a base surface 226 extending between the planar bottom surface222 and the curved top surface 224.

Each channel 50, 52 includes an aperture 228 formed in the base surface226 and configured to receive a corresponding protrusion 234 formed oneach of the collar components 214, as described in greater detail below.In the illustrative embodiment, the aperture 228 does not extend throughthe stem component 216. In other embodiments, however, the aperture 228extends from the base surface 226 of channel 50 to the base surface 226of channel 52.

As shown in FIG. 12, the system 210 includes a stabilizing collar 230and a trochanter collar 232 that are configured to be selectivelycoupled to the stem component 216. In the illustrative embodiment, eachof the collars 230, 232 is configured to engage a surgically preparedproximal surface 132 of the patient's femur 130 when the femoralprosthesis 212 is positioned in the patient's femur 130.

In the illustrative embodiment, each of the collars 230, 232 includes abase 56 that is configured to engage with the stem component 216.Similar to the collars described above, the base 56 of each collar 230,232 includes the superior surface 58, the inferior surface 60, the outersurface 62, and the inner wall 64 that defines the slot 66 in each ofthe collars 230, 232. The stabilizing collar 230 has an opening 68formed at a lateral end 70 of its base 56. The base 56 of thestabilizing collar 324 also includes a platform 72 that is positionedopposite the opening 68 and a pair of arms 74, 76 that extend laterallyfrom the platform 72 along the slot 66.

Each base 56 also includes a pair of protrusions 234 are formed on theinner wall 64 of the base 56. The protrusions 234 are configured to actas retainers to mechanically secure each collar component 214 to thestem component 216. The protrusions 234 may be used in addition to thepress-fit connection between the collar components and the stemcomponent described above. In other embodiments, however, theprotrusions 234 may be used on their own to couple the collar components214 to the stem component 216.

The protrusions 234 are sized to be received into the apertures 228formed in the base surfaces 226 of each channel 50, 52. The protrusions234 are positioned such that when a collar component 214 is coupledsecurely to the stem component 216, the protrusions 234 are receivedinto the each aperture 228. A portion of the superior surface 58 of thebase 56 extends superiorly away from the inferior surface 60 of the base56 to form the structure that supports the protrusions 234. Eachprotrusion 234 extends inwardly from the inner wall 64.

As shown in FIGS. 15-16, the illustrative slot 66 of the trochantercollar 232 is surrounded by the inner wall 64 such that the slot 66 is aclosed slot. The trochanter collar 232 includes the base 56 and theflange 90 extending away from the lateral end 92 of the base 56.

The femoral prosthesis 212 may be assembled in the manner describedabove. For example, the stabilizing collar 230 may be advanced along thelongitudinal axis 55 such that the pair of arms 74, 76 of thestabilizing collar 230 are received into the groove 220. The stabilizingcollar 230 is advanced until the pair of protrusions 234 are receivedinto each aperture 228 formed in the groove 220.

Referring now to FIGS. 20-21, another embodiment of a modular femoralprosthesis system (hereinafter system 310) of a hip prosthesis is shown.Some of the features of FIGS. 20-21 are similar to the featuresdescribed in the embodiments shown in FIGS. 1-19. For such features, thereference numbers from the embodiments described above will be used toidentify those features in FIGS. 20-21. Like the embodiments of FIGS.1-19, the femoral prosthesis system 310 may be utilized to assemble afemoral prosthesis 312 customized to the needs of each patient.

The femoral prosthesis system 310 includes a femoral stem component 316configured to be implanted into a patient's femur 130, the femoral headcomponent 18 configured to be attached to the femoral stem component316, a plurality of modular collar components 314 configured to beseparately and selectively secured to the femoral stem component 316,and a fastener 320 configured to secure a collar component 314 to thestem component 316. In use, an orthopaedic surgeon may assemble afemoral prosthesis 312 using the various components before implantingthe assembled femoral prosthesis 312 in the patient's femur 130.

As shown in FIG. 20, the stem component 316 includes the neck 26, theelongated body 28 configured to be received in a surgically-preparedcavity of the patient's femur 130, and the trunnion 30 extendingsuperiorly and medially from the neck 26. The shoulder 32 connects theneck 26 to the elongated body 28. In the illustrative embodiment, thestem component 316 includes the groove 220 that is sized to receiveportions of each collar component 314 to secure the collar component 314to the stem component 316 via the fastener 320.

As shown in FIG. 21, an aperture 322 extends through stem component 316between the base walls 54 of each channel 50, 52. The aperture 322 isconfigured to receive the fastener 320 and secure one of the collarcomponents 314 to stem component 316. The aperture 322 is configured toalign with through-holes 328 formed in the base 56 of the collarcomponents 314.

As shown in FIG. 20, the system 310 includes a stabilizing collar 324and a trochanter collar 326 that are configured to be selectivelycoupled to the stem component 316. In the illustrative embodiment, eachof the collars 324, 326 is configured to engage a surgically preparedproximal surface 132 of the patient's femur 130 when the femoralprosthesis 312 is positioned in the patient's femur 130. Each of thecollars 324, 326 includes a base 56 that is configured to engage withthe stem component 316. The base 56 includes the superior surface 58,the inferior surface 60, the outer surface 62, and the inner wall 64that defines the slot 66 in each of the collars 324, 326. Thestabilizing collar 324 has an opening 68 formed at a lateral end 70 ofits base 56. The base 56 of the stabilizing collar 324 also includes aplatform 72 that is positioned opposite the opening 68 and a pair ofarms 74, 76 that extend laterally from the platform 72 along the slot66.

A pair of through-holes 328 sized to receive the fastener 320 are formedin the base 56. Each of the through-holes 328 extend from a firstopening 330 formed in the inner wall 64 of the base 56 to a secondopening 332 formed in outer surface 62 of the base 56. One of thethrough-holes 328 of each collar component 314 include a lip surface 334configured to engage with a corresponding flange surface on the fastener320. The pair of through-holes 328 are positioned on the base 56 suchthat when the collar component 314 is coupled to the stem component 316,the pair of through-holes 328 align with the aperture 322. A portion ofthe superior surface 58 of the base 56 extends superiorly away from theinferior surface 60 of the base 56 to form the structure that definesthe through-holes 328.

The fastener 320 includes a fastener head 336 and a plurality ofcantilevered arms 338 extending distally away from the fastener head336. In other embodiments, however, the cantilevered arms may not alwaysbe present. For example, the fastener 320 may include ridges that arereceived into corresponding threads formed in the collar components 314and the stem component 316. Each of the cantilevered arms 338 include anarm body 340 and a flange 342 positioned at a distal end 344 of each armbody 340. Each flange 342 includes a flange surface 346 configured toengage with the lip surface 334 of each collar component 314. Thecantilevered arms 338 are configured to be deflected when the fastener320 is used to secure a collar component 314 to the stem component 316.In the illustrative embodiment, the fastener 320 is formed from animplantable metallic material such as, for example, stainless steel,cobalt chromium, or titanium. In other embodiments, however, thefastener 320 may be made of a polymeric material.

As discussed above, the fastener 320 is configured to secure one of thecollar components 314 to the femoral stem component 316. In use, acollar component 314 is selected from the plurality of collar components314 to secure to the femoral stem component 316. The selected collarcomponent 314 is positioned on the femoral stem component 316 such thatthe through-holes 328 of the selected collar component 314 align withthe aperture 322 formed in the stem component 316. Once aligned, thefastener 320 is advanced through the through-holes 328 and the aperture322 to secure the selected collar component 314 in a fixed positionrelative to the stem component 316. As the fastener 320 passes throughthe first through-hole 328, the cantilevered arms 338 of the fastener320 are deflected inwardly. After the flange 342 of each cantileveredarm 338 passes through the second through-hole 328 of the selectedcollar component 314, each cantilevered arm 338 expands outwardly toengage the lip surface 334 of the selected collar component 314.Specifically, the flange surface 346 of each cantilevered arm 338engages the lip surface 334 to secure the selected collar component 314to the stem component 316.

Referring now to FIGS. 22-24, another embodiment of a modular femoralprosthesis system (hereinafter system 410) of a hip prosthesis is shown.Some of the features of FIGS. 22-24 are similar to the featuresdescribed in the embodiments shown in FIGS. 1-21. For such features, thereference numbers from the embodiments described above will be used toidentify those features in FIGS. 22-24. Like the embodiments of FIGS.1-21, the femoral prosthesis system 410 may be utilized to assemble afemoral prosthesis 412 customized to the needs of each patient.

The femoral prosthesis system 410 includes a femoral stem component 416configured to be implanted into a patient's femur 130, the femoral headcomponent 18 configured to be attached to the femoral stem component416, a collar component 414 configured to be selectively secured to thefemoral stem component 416, and the fastener 320 configured to secure acollar component 414 to the stem component 416. In use, an orthopaedicsurgeon may assemble a femoral prosthesis 412 using the variouscomponents before implanting the assembled femoral prosthesis 412 in thepatient's femur 130.

The stem component 416 includes a groove 422 formed in the shoulder 32of the stem component 416. The groove 422 is sized to receive portionsthe collar component 414 and to secure the collar component 414 to thestem component 416 via the fastener 320. The groove 422 includes thepair of channels 50, 52 that are defined in the anterior surface 36 andthe posterior surface 38, respectively, of the shoulder 32. The channels50, 52 extend from open ends 46 defined in the medial surface 34 of theshoulder 32. Each of the channels 50, 52 extends along the longitudinalaxis 55 that extends transverse to the longitudinal axis 45 of thetrunnion 30.

The channels 50, 52 are defined by base walls 54 that extend inwardlyfrom openings defined the surfaces 36, 38. The base walls 54 include theplanar bottom surface 222 that extends transversely to the longitudinalaxis 45 of the trunnion 30, a top surface 424, and the base surface 226extending between the planar bottom surface 222 and the top surface 424.The top surface 424 includes a first planar portion 426, a second planarportion 428, and a curved portion 430 extending therebetween.

An aperture 432 is formed in the base surface 226 of each of thechannels 50, 52. As shown in FIG. 23, the aperture 432 extends throughthe stem component 416 and is configured to align with the through-holes328 formed in the collar component 414.

The collar component 414 is configured to engage a surgically preparedproximal surface 132 of the patient's femur 130 when the femoralprosthesis 412 is positioned in the patient's femur 130. The collarcomponent 414 may be formed from a rigid polymer such aspolyetheretherketone (PEEK). In the illustrative embodiment, the collarcomponent 414 includes a base 56 that is configured to engage with thestem component 216. The base 56 includes the superior surface 58, theinferior surface 60, the outer surface 62, and the inner wall 64 thatdefines the slot 66. The collar component 314 also includes a lipsurface 434 configured to engage the flange surface 346 of the fastener320.

As discussed above, the fastener 320 is configured to secure the collarcomponent 414 to the femoral stem component 416. The collar component414 is positioned on the femoral stem component 416 such that thethrough-holes 328 of the collar component 414 align with the aperture432 formed in the stem component 416. Once aligned, the fastener 320 isadvanced through the through-holes 328 and the aperture 432 to securethe collar component 414 in a fixed position relative to the stemcomponent 416. As the fastener 320 passes through the first through-hole328, the cantilevered arms 338 of the fastener 320 are deflectedinwardly. After the flange 342 of each cantilevered arm 338 passesthrough the second through-hole 328 of the selected collar component314, each cantilevered arm 338 expands outwardly to engage the lipsurface 434 of the collar component 414. Specifically, the flangesurface 346 of each cantilevered arm 338 engages the lip surface 434 tosecure the collar component 414 to the stem component 416.

While the disclosure has been illustrated and described in detail in thedrawings and foregoing description, such an illustration and descriptionis to be considered as exemplary and not restrictive in character, itbeing understood that only illustrative embodiments have been shown anddescribed and that all changes and modifications that come within thespirit of the disclosure are desired to be protected.

There are a plurality of advantages of the present disclosure arisingfrom the various features of the method, apparatus, and system describedherein. It should be noted that alternative embodiments of the method,apparatus, and system of the present disclosure may not include all ofthe features described yet still benefit from at least some of theadvantages of such features. Those of ordinary skill in the art mayreadily devise their own implementations of the method, apparatus, andsystem that incorporate one or more of the features of the presentinvention and fall within the spirit and scope of the present disclosureas defined by the appended claims.

1. A method for performing a hip arthroplasty, the method comprising: resecting a proximal end of a patient's femur to form a planar proximal surface, selecting a femoral stem component having a neck, an elongated body extending distally from the neck, and a trunnion configured to receive a femoral head component extending medially and proximally from the neck, inserting a broach through the planar proximal surface to define a passageway sized to receive the selected femoral stem component, selecting a collar component from a plurality of collar components, each collar component including an inferior surface configured to engage the planar proximal surface of the patient's femur, securing the selected collar component to the femoral stem component such that the inferior surface of the collar component extends transverse to a longitudinal axis of the trunnion of the femoral stem component, and implanting the femoral stem component in the patient's femur such that the inferior surface of the selected collar component engages with the planar proximal surface of the patient's femur.
 2. The method of claim 1, wherein: selecting the collar component further includes selecting a first collar component from the plurality of collar components, the first collar component including a base having the inferior surface configured to contact a surgically prepared proximal surface of the patient's femur, the base comprising (i) a platform and (ii) a pair of arms extending away from a lateral end of the platform, the pair of arms cooperating to form a slot having an opening defined at a lateral end of the base, the slot being sized to receive the stem component, and securing the selected collar component to the femoral stem component further includes advancing the first collar component along a groove axis defined by a groove formed in the stem component, the groove axis extending transverse to the longitudinal axis defined by the trunnion.
 3. The method of claim 2, wherein advancing the first collar component further comprises advancing the first collar component along the groove axis until the inner surface of the first collar component engages with the groove surface of the stem component.
 4. The method of claim 1, wherein selecting the collar component further includes selecting a second collar component from the plurality of collar components, the second collar component including (i) a base having the inferior surface configured to contact a surgically prepared proximal surface of the patient's femur and defining a slot sized to receive the stem component and (ii) a flange extending away from a lateral end of the base, the flange being configured to secure the second collar component in a fixed position relative to a trochanter of the patient.
 5. The method of claim 4, wherein securing the selected collar component to the femoral stem component further comprises: inserting a distal tip of the stem component into the slot of the second collar component, advancing the second collar component proximally along a body axis defined in the stem component, and engaging a groove surface that defines a groove formed in the stem component with the inner surface of the second collar component.
 6. The method of claim 4, further comprising: securing a trochanteric reattachment device to the patient's trochanter, the trochanteric reattachment device including a body and a plurality of cables, threading the plurality of cables through a plurality of passageways extending through the flange of the second collar component, and securing the threaded cables to the body of the trochanteric reattachment device.
 7. The method of claim 4, wherein the base includes a superior surface extending between a medial end of the base and the lateral end of the base and an inner wall extending between a first opening formed in the superior surface and a second opening formed in the inferior surface to define the slot sized to receive the stem component, and wherein the flange includes a medial surface that abuts and extends away from the superior surface of the base and cooperates with the base to define a non-orthogonal angle relative to the superior surface of the base. 